Liquid distributing system



June 15, 1954 B. c. w. HAGELIN ETAL LIQUID DISTRIBUTING SYSTEM OriginalFiled May 13, 1949 FIG. 5. F/GJ.

llllllll Patented June 15, 1954 2,681,253 ICE 2,681,253- LI'QUIDDISTRIBUTING SYSTEM Boris Caesar- Wilhelm. Ha

Staffan Ljungdahl, Ake

Sweden Original application May 13,, 1949,, Serial gelin, Stockholm, and

slund; near- Stockholm,

93,042. Dividedand this application December 27, 1-951; Serial'No.263,662

Claims priority,

8 Claims.

The present application is divided out from our oopending applicationSerial No. 93.042, filed May 13, 1 949, entitledMethod of and Means forDistributing Liquid Matters.

The invention relates to a liquid injection device for use in connectionwith liquid distributing system in which. the liquid fed to theinjectiondevices is subjected to a pulsating pressure. example of such a systemis described in our copcnding application Serial No. 93,042, filed May13, 1949.

An object of theinvention is to provide a liquid injection devicehavingmeans operableunder the control of the pulsating pressure of the liquidfed to the device for effecting a forced ejection of the liquid atintervals corresponding to the frequency of the pressure pulsations oithe-liquid.

Another object of the invention is to provide such a liquid injectiondevice having means for adjusting thecapacity of the device.

According to a feature of the invention the injection device is of apump like structure, comprising as main elements a cylinder and areciprocable plunger therein with connections and stroke of the plunger,causing. it to eject a quantity of liquid supplied to the cylinder bythepreceding impulse.

According to another feature of the invention the injectionv device isprovided with a passage extending between the cylinder chamber at therear end of the plunger adapted to be acted on by the pressure impulsesand the cylinder chamberat the front end of the plunger incom-munication with the outletopeni-ng of the" cylinder, and anautomatic valve for controlling the how of liquid through said passage,so as to allowsuo-h flow during the return stroke of the plunger Whileinterrupting it during the operativestrolre ofthe plunger.

A further feature of the invention related to said last-mentionedfeature resides in the provision of a non-returnvalve between the inletof the cylinder and the cylinder chamber at the rear end of the plungerforallowingthe'operation of said automatic valve under the influence ofpressure differences inside the device.

In the accompanying drawing two forms of the invention are illustrated"by way of example.

Figs. 1 and 2. are. longitudinal sections of an embodiment in theplunger,

Fig. 3 isanaxial section of theother embodimerit and Fig. dis a portionof Fig; 2 on a larger scale.

With reference to Figs. 1 and 2, the reference ally positioned inletZilandan outlet 28, 29 in its bottom end. Preferably, .the outlet maytake theshape of a spraying nozzle; especially where two end positionsof the a cylinder, having a laterapplication Sweden May 15,1948

. non-returnvalve 7 channel l. 26, but since the device is to be used ina fuel distributing system. Slidably mounted in the cylinder is. a.plunger 25 which may reciprocate between the bottom of the cylinder andan upper stop formed by a screw 22 which may be controlled from outsidethe cylinder. The plunger is formed be:- tween its ends with an annularrecess 23 in the circumferential surface in the middle portion of whichan annular projection 25' is made, the upper and lower edges of whichare obliquely undercut so as to form sharp knife-edges as. best shown at25 and 25 respectively, in Fig. 4. Placed in said recess 23 theprojection 25 is an elastic sleeve 24 having inwardlyprojecting flangesat its ends which embrace the upper and lower edges of the projection25, preferably under a certain initial pressure. By this means a highsealing effect is ob tained at the sharp edges of projection 25. Themiddle thin portion of sleeve 24 covers theopenings of two channelsformed in the plunger, viz. an upwardly extending channel- 26 openinginto the top surface of the plunger and a extending channel 27' openinginto the bottom surface of the plunger. Formed in the bottom or" thecylinder in register with the channel 27 is a boring 28 ending in anarrow aperture 29, which as already stated may be shaped like aspraying nozzle.

The lower end portion of the plunger is of a reduced diameter and issurrounded by a spring 56 resting on the bottom of the cylinder whichtends to force the plunger upwardly. The annular recess 23 communicateswith the space above the plunger through a channel it having a widenedcentral portion in which a non-return valve 42 is inserted for allowinga fiow of liquid from liquid to be ejected at each operative stroke ofplunger. The operation is as follows:

The inlet Let it now be" assumed that liquid is contained in thecylinder including the lower cylinder chamber, below the bottomend ofthe plunger.

Assoon as a pressure impulse reaches the inlet 20 the pressure of saidimpulse is imparted through recess 23 and connection 41 past the 32 upinto the cylinder chamber above the plunger. In such case the pressureprevailing on the external surface of sleeve 24 will be equal to thepressure prevailing on'that surface thereof which covers the opening ofthe-operative pressure surso asto snugly surround downwardly face of thesleeve is much larger on the external surface of the sleeve than it ison the internal surface thereof, the bypass channel will remain closedas long as the pressure is acting. The pressure in the cylinder chamberabove the plunger will consequently force the plunger downwards, therebyforcing the liquid in the cylinder chamber below the plunger out throughthe outlet 2%, 2s by an elevated pressure. When the plunger reaches itslowermost position, as shown in Fig. 2, its downward movement, that is,its operative stroke is ended. As soon as the pressure impulse ceases,the return spring as will raise the plunger. Since the non-return valve42 prevents the liquid from returning to the recess 23 and the inlet 29,a pressure above atmospheric will be attained on the top surface of theplunger and since no external pressure acts on the elastic sleeve, thepressure resulting from the liquid in the bypass channel section 25 willforce the middle portion of the'sleeve outwards, so that during theupward, that is, return stroke of the plunger fuel may pass from channelsection 25 to channel section 21 and reach the cylinder chamber belowthe plunger.

Fig. 3 illustrates the construction of the liquid injection device morein detail. The reference numerals are the same as those used in Figs. 1and 2. In addition to the elements shown in Figures 1 and 2, Fig. 3shows amongst others a filter 34 for the fuel entering through the inlet26, furthermore there are packings 35 and 35 provided in combinationwith the plunger on both sides of the annular recess 23, and vents 35leading from the spaces above and below the plunger in the pump casing16. The connection between the screw 22 and the pointer 43 comprises arounded rack 3'! formed integrally with the screw 22 and axiallyextending teeth, not shown, of a transverse shaft 38 which in its turncontrols the pointer.

In this embodiment the outlet boring 23 is formed with a reduced areaapproximately between its upper and lower ends, as shown at 23 andinserted in the wider lower portion of boring 2,8 is a non-return valve28 loaded by an upwardly acting spring 28 The non-return valve 28prevents dribbling in the intervals between the ejections, since saidvalve is normally closed and opened only under the action of the risingpressure in the lower cylinder chamber during the downward stroke of theplunger.

We claim:

1. A liquid injection device of the class specified comprising incombination, a casing having an inlet for a liquid adapted to besupplied thereto under a pulsating pressure and an outlet for saidliquid, a reciprocable plunger in said casing adapted to be operated bythe pressure impulses of the liquid supplied to said inlet for eifectinga forced ejection of a quantity of liquid through said outlet at eachoperation stroke of said plunger, a bypass being provided inside thedevice between the end surface of the reciprocable plunger adapted to beacted on by the pressure impulses and the outlet, an automatic valve forcontrolling the flow of liquid through said bypass, and a non-returnvalve inserted between the inlet and said liquid-operated area of thereciprocable plunger, said automatic valve being adapted to interruptthe flow of liquid through the bypass when the liquid pressure in frontof the non-return valve is higher than the pressure behind said valve,andto, allow the flow of liquid portions of with an annular recessthrough the bypass when the pressure behind the non-return valve ishigher than the pressure in front thereof.

2. In a liquid injection device in combination, a cylindrical casinghaving a lateral inlet for a liquid adapted to be supplied thereto undera pulsating pressure and an outlet for said liquid at one end, areciprocable plunger in said casing for discharging the liquid throughsaid outlet at an elevated pressure, a passage being provided betweenthe liquid inlet and the end of the plunger remote from the outlet forallowing the liquid to displace the plunger towards the outlet, anon-return valve for controlling said passage, the plunger havingfurther a by-pass formed in it which comprises two channel sectionsextending from opposite ends of the plunger to spaced points of thecircumference thereof, and an elastic sleeve snugly fitting around theplunger so as to cover said points with its external surface. exposed tothe pressure of the liquid at the inlet.

3. A liquid injection device as claimed in claim 2, and in which theplunger is formed on its circumierence with annular knife edges to actas tightening elements in cooperation with the elastic sleeve, saidknife edges being engaged by said sleeve under an initial pressure forsecuring a high sealing effect per unit of area.

4. A liquid injection device as claimed in claim 2, and in which theplunger is under the control of a spring action for eifecting its returnstroke, an adjustable stop being provided for determining thetermination of said stroke and thus the quantity of liquid to be ejectedat next operative stroke.

5. A liquid injection device as claimed in claim 2, and in which theplunger is externally formed with an annular recess between its ends forreceiving the elastic sleeve, said recess being in permanentcommunication with the liquid inlet of the casing.

6. A liquid injection device as claimed in claim 2, and in which theplunger is externally formed between its end in per manent communicationwith the liquid inlet of the casing, characterized by the furtherfeature that the plunger is formed with a channel between said annularrecess and the end of the plunger to be acted on by the pressureimpulses, the non-return valve being mounted in said passage in such away as only to allow a flow of liquid in the direction from said inletto said end of the plunger while positively preventing any flow ofliquid in the reverse direction.

7. A liquid injection device as claimed in claim 2, and. in which theoutlet of the cylindrical casing is provided with a spraying nozzle.

8. A liquid injection device as claimed in claim 2, and in which theoutlet of the cylindrical casing is provided with a spraying nozzle,characterized by the provision of a non-return valve in front of saidspraying nozzle.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,228,335 McClelland May 29, 1917 1,543,178 Meili June 23, 1922,389,492 Edwards Nov. 20, 1945 2,506,528 Webb, Jr., et a1 May 2, 19502,569,233 Dickson et al Sept. 25, l951 FOREIGN PATENTS Number CountryDate 594,6 l4 .Germany Nov. 2'7, 1932

